Hi,
sorry iff this is the wrong forum to ask this question. But i just need a few simple lines of php code, and i cant seem to find the right commands. Its rater simple i think. 1st, i have these strings already included: $username, $newpass. I also have this line in a TEXT file:

$username n8427rn873

How can i replace n8427rn873 with $newpass??? And those random characters (encryption) will be different each time the script is exectuted. So is there a way to 'count' right the number of characters in $username? then replace everything after it with $newpass? Maybe some variation of str_replace? Thanks